CopyOnWriteArrayList removeIf() method in Java with Examples

The removeIf() method of CopyOnWriteArrayList removes the element from this CopyOnWriteArrayList that satisfies the specified condition.
Syntax:
public boolean removeIf (Predicate<E> filter)
Parameters: This method accepts a mandatory parameter filter which is the predicate value based on which elements are removed from this List.
Return Value: This method returns a boolean value such as true, if the CopyOnWriteArrayList is changed. Else this method returns false.
Exceptions: This method throws NullPointerException if the specified Predicate filter is null.
Below program illustrates the removeIf() function of CopyOnWriteArrayList class :
// Java Program to illustrate the CopyOnWriteArrayList// removeIf() method in Java import java.util.concurrent.CopyOnWriteArrayList;import java.util.*; public class GFG { public static void main(String[] args) { // create object of CopyOnWriteArrayList CopyOnWriteArrayList<Integer> ArrLis = new CopyOnWriteArrayList<Integer>(); // Add elements ArrLis.add(2); ArrLis.add(3); ArrLis.add(4); ArrLis.add(7); ArrLis.add(6); ArrLis.add(9); // print CopyOnWriteArrayList System.out.println("CopyOnWriteArrayList: " + ArrLis); // if a number in the List is // divisible by 3, then remove it ArrLis.removeIf(number -> number % 3 == 0); // print updated CopyOnWriteArrayList System.out.println("Updated CopyOnWriteArrayList: " + ArrLis); }} |
Output:
CopyOnWriteArrayList: [2, 3, 4, 7, 6, 9] Updated CopyOnWriteArrayList: [2, 4, 7]
// Java Program to illustrate the CopyOnWriteArrayList// removeIf() method in Java import java.util.concurrent.CopyOnWriteArrayList;import java.util.*; public class GFG { public static void main(String[] args) { // create object of CopyOnWriteArrayList CopyOnWriteArrayList<String> ArrLis = new CopyOnWriteArrayList<String>(); // Add elements ArrLis.add("Lazyroar"); ArrLis.add("GFG"); ArrLis.add("Geeks"); ArrLis.add("Gfg"); // print CopyOnWriteArrayList System.out.println("CopyOnWriteArrayList: " + ArrLis); try { // This will throw NullPointerException ArrLis.removeIf(null); } catch (Exception e) { System.out.println(e); } }} |
Output:
CopyOnWriteArrayList: [Lazyroar, GFG, Geeks, Gfg] java.lang.NullPointerException



